Preaheat the oven to 350 degrees farenheit. Grease a 9 inch cake pan, set aside.
In a large mixing bowl, cream the butter and sugars together until light and fluffy. Beat in the egg. Stir in the vanilla extract, bourbon and buttermilk until combined. Mix together flour, baking powder and salt. Add flour mixture to creamed mixture. Spread batter into prepared cake pan.
Bake in preheated oven until lightly browned on top, 35 to 40 minutes. Remove cake from oven, and let cake cool completely.
Whipped Cream
In a medium bowl, whip cream until soft peaks form. Add sugar and continue whipping until it forms stiff peaks. Gently fold in the bourbon and vanilla extract. Chill until ready to assemble the cake.
Peaches
In a medium bowl mix together the peaches, bourbon, sugar, and cinnamon. Let it sit out for at least a half hour, or refrigerate for several hours so that the fruit takes on the flavor of the bourbon mixture.
Assembly
Once the cake is completely cooled, spread the whipped cream over the cake in an even layer. Top with the peach mixture. Serve immediately, or keep covered in the refrigerator until serving.